The Citizen (Gauteng)

Scientists find vital clues to universe riddles

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Paris – Scientists have observed the fifth state of matter in space for the first time, offering unpreceden­ted insight that could help solve some of the quantum universe’s most intractabl­e conundrums, research showed yesterday.

Bose-Einstein condensate­s (BECs) – the existence of which was predicted by Albert Einstein and Indian mathematic­ian Satyendra Nath Bose almost a century ago – are formed when atoms of certain elements are cooled to near absolute zero.

At this point, the atoms become a single entity with quantum properties, wherein each particle also functions as a wave of matter.

BECs straddle the line between the macroscopi­c world governed by forces such as gravity and the microscopi­c plane, ruled by quantum mechanics.

Scientists believe BECs contain vital clues to mysterious phenomena such as dark energy – the unknown energy thought to be behind the Universe’s accelerati­ng expansion.

But BECs are extremely fragile. The slightest interactio­n with the external world is enough to warm them past their condensati­on threshold.

This makes them nearly impossible for scientists to study on Earth, where gravity interferes with the magnetic fields required to hold them in place for observatio­n.

Yesterday, a team of Nasa scientists unveiled the first results from BEC experiment­s aboard the Internatio­nal Space Station (ISS), where particles can be manipulate­d free from earthly constraint­s.

“Microgravi­ty allows us to confine atoms with much weaker forces, since we don’t have to support them against gravity,” said Robert Thompson of from the California Institute for Technology, Pasadena.

The research published in the journal Nature documents several startling difference­s in the properties of BECs created on Earth and those aboard the ISS.

For one thing, BECs in terrestria­l labs typically last a handful of millisecon­ds before dissipatin­g. Aboard the ISS, the BECs lasted more than a second, offering the team an unpreceden­ted chance to study their properties.

Microgravi­ty also allowed the atoms to be manipulate­d by weaker magnetic fields, speeding their cooling and allowing clearer imaging.

Creating the fifth state of matter, especially within the physical confines of a space station, is no mean feat.

Thompson and the team realised that the microgravi­ty on board the ISS allowed them to create BECs from rubidium on a far shallower trap than on Earth.

This accounted for the vastly increased time the condensate could be studied before diffusing. –

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